Porous ceramic materials have many desirable properties, such as light weight, high surface area to weight ratio, and high chemical and thermal stability. As a result, applications of such ceramic materials extend into various fields, including environmental, energy, biotechnology, and others. For example, porous alumina may be used in a wide range of applications, such as separators, filters, adsorbents, abrasives, catalysts, and catalyst supports, and the desired porosity may depend on the particular application.
Various properties of the porous ceramic materials may depend on the material itself, techniques used to form the material, and on the desired application. Often the porous ceramic material includes relatively small diameter pores and low pore volume, resulting in a high pressure drop across the ceramic material. When such materials are used in a reactor, such as a fixed bed reactor, the high pressure drop may be disadvantageous.
Several methods for the fabrication of porous ceramics, such as porous alumina, have been studied. For example, template-directed approaches have been employed to form nano-/microscale porous structures. Recently, a great deal of effort has been placed on the synthesis of mesoporous alumina with a high specific surface area and large pore volume using various templates, including surfactants, carboxylic acids, and single organic molecules. However, these techniques have not led to the synthesis of porous alumina monoliths and particles with crystallized frameworks and controlled wall thickness. Accordingly, improved techniques for forming highly porous ceramic materials with relatively large pores are desired.